Johnny Upgrade

"Johnny 7823263, Let me tell you about something that happened long ago. There was once a Johnny 1, he lived for about two seconds too weak to move. Then he died. So then there was Johnny 2, he just randomly appeared out of nowhere, he shared the same lifespan as Johnny 1 but he could move. He moves toward a floating disk of gold. When he touched it it dissipated and he felt a sense of accomplishment. Then he died. Then there was Johnny 3, He could live for twice as long as the Johnnys who came before him. He live for four glorious seconds, picking up three majestic discs. For those four seconds he felt invincible. Then he died."
"So where are you going with all of this?"
"There were 7823262 Johnnies before you. And there will be thousand after you, goodbye my son"
*Johnny 7823263 explodes into bones and guts*

Hey, I've just killed the boss and saved the world. Now to retire and enjoy the remaining 25 seconds of my life to the fullest.

Hmm. I am an small human that is too weak to jump or even move. I have no weapons and a 2 second lifespan. What should i do with my life? I know, i will become a SUPERHERO!
Makes sense! :)

For those struggling with the boss: Dodge his first bullets. Then when canons rotate stand exactly below him to dodge those ones, too. When he stops shooting run away, cause he will drop to the ground. When he dropped you can shoot him exactly once, any more shots won't hurt him. Repeat four times and you won. Can be done easily without being hit even once, but you even have enough time to try to get to the boss with as many hearts as possible if you are unsure.

Not bad - short, dash of humor, decent controls, solid boss. Fledging, but enjoyable.